Suspension-bridge



(No Model.)

D. B. McHENRY. SUSPENSION BRIDGE.

No. 524,486. Patented Aug. 14, 18 94.

aI/(Mm UNITED STATES PATENT OFFICE.

DAVID B. MGHENRY, OF GRENADA, MISSISSIPPI.

SUSPENSION-BRIDGE.

SEEGIFICATION forming part of Letters Patent No. 524,486, dated August14, 1894.

Application filed February 13,1894. Serial No. 500,084. (No model.)

To all whom it may concern:

Be it known that I, DAVID B. MOHENRY, a citizen of the United States,and a resident of Grenada, in the county of Grenada and State ofMississippi, have invented certain new and useful Improvements inSuspension-Bridges; and I do declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, and to letters ofreference marked thereon, which form a part of this specification. t

Figure 1 of the drawings is a side elevation of a bridge embodying myinvention. Fig. 2

is a transverse vertical section on the line 0c--oc, Fig. 1. Fig. 3 is aplan view of a portion ofthe bridge with the flooring partially removed.Fig. 4 is a detail view showing a modified form of hanger, and Fig. 5 isa similar View of aportion of one of theupper suspension-rods.

This invention has relation to certain-new and useful improvements insuspension bridges, and it consists in the novel construction andcombination of parts, all as hereinafter described and pointedout in theap pended claims.

My object is to provide a bridge of the above named character, designedfor comparatively short spans, of greatly simplified construction andcapable of being erected at a comparatively small cost, the parts beingso constructed and combined as to unite the maximum of strength with theminimum of lightness.

Referring to the accompanying drawings, the letters A, A, designate thepiers 0r abutments, which are usually constructed in the followingmanner: Sunk in the ground under each pier at the proper distance fromeach other, are .two mud sills B, B, which lie parallel with the lengthof the span, and which are anchored in any suitable manner. These sillsform the supports for the upright posts or piers A, A, which are securedthereto, and braced by the heavy struts G, C, on the span side. 0', Care anchor rods from the posts to the mud sills. The two mud sills maybe connected by suitable trusses or beams D.

E, E, designate the lower horizontal longitudinal suspension rods one ateach side, whose end portions pass through the struts O, uprights A, A,and through bearing plates E, and are secured by nuts, or in any otherapproved manner. Each of said rods is formed in two or more sectionsunited by turn buckles F.

G, G, designate the upper suspension rods, also formed each in two ormore sections, connected in the same manner as the rods E, E, and alsosecured in the uprights. These rods G,-G, are not parallel with thelower rods, but have a downward curve to the center.

The rods G and E on each side are connected by a series of hangers H.For spans of less than thirty feet, these hangers may consist simply ofa rod having a hook at each end for engagement with the respectivesuspension rods. For spans of over thirty feet. the hangers shouldhowever be constructed as shown in Fig. 4, in two sections 71., h,connected by a turn buckle h, and having eyes 71 for engagement with thesuspension rods. The upper rods are usually corrugated where they areengaged by said eyes in order to pre vent slipping of the hangers.

The rods G, G, form the supports for a series of transverse floor joistsI, upon which rest longitudinal floor beams J. The joists I are bracedby diagonal crossing braces K. The flooring boards L are laid obliquelyon the floor beams J.

M, M, are two truss beams extending transversely underneath the centralportion of the span, and supported by suspension rods N from the piers.The said rods are usually made each in two or more sections, connectedat the center or at equal distances therefrom by a turn buckle O. Thelongitudinal fioor beams J, J, have a supportin the struts O, C.

It will be observed that by the employment of the parallel beams M M,placed at some distance apart, a secure support is provided for thecentral portion of the bridge, and arching of the lower suspension rodsor cables is avoided. Also that the suspension chains N extend directlyto the piers, which receive directly the strain of said cables, and thusdoes away with the necessity for the additional cables to which similarrods have sometimes been attached, and reducing the number of partsrequired without detracting from the strength. 7

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a suspension bridge, the piers, the lower horizontal suspensionrods, the upper suspension rods, the series of hangers connecting saidupper and lower rods upon each side, the parallel transverse centralbeams M M, at some distance from each other, and suspension rods Nsupporting said beams, and connected directly to the piers,substantially as specified.

2. In a suspension bridge, the combination with the piers or abutments,of the lower suspension rods E, E, the upper suspension rods 77 DAVID B.Moi-IENRY.

Witnesses:

G. T. W001), R. B. RICE.

